Rivers

For rivers
and streams GLOBIO includes cause-effect relationships for two environmental
drivers.

Land use
and eutrophication

The first
environmental driver for rivers and streams is ‘land use and eutrophication’.
Over 50 studies on biodiversity in rivers and streams in catchments with
different types of land use (forest, agricultural, urban etc.) were found in
the literature. Twelve of these expressed their results in a sufficiently
quantitative way to be expressed as MSA. These data were fitted by linear
regression (see figure). The average results for
different biotic groups point to a 0.34 – 0.82 % MSA loss per % land use, with
fish being the most sensitive.

The relationship between catchment land use and river biodiversity

Change in hydrological regime

The second
driver for rivers and streams is the change in hydrological regime.
Quantitative data from about 20 studies on biodiversity in rivers at different
degrees of flow deviation (e.g. by dams, water extraction or climate change)
were combined and expressed as MSA. The data were fitted by logistic
regression.